Discover Life | All Living Things | IDnature guides | Mammalia | Vespertilionidae | Corynorhinus rafinesquii

Species Description

• Adult total length: 3 5/8 - 4 1/4 in. (92 - 106 mm)

• Tail: 1 5/8 - 2 1/8 in. (41 - 54 mm)

• Hind foot: 1/4 - 1/2 in. (8 - 12 mm)

• Weight: 1/5 - 1/3 oz. (6 - 10 mm)

• Physical Characteristics: Bats are unique among mammals because their forelimbs are specialized for true flight. Flight membranes, which are actually extensions of the skin of the back and belly, connect the body with the wings, legs, and tail. Unlike birds, bats use both legs and wings during flight. Other modifications for flight include greatly elongated fingers to provide support for the wing membrane, a keeled sternum for the attachment of the enlarged flight muscles, and fusion of some vertebrae. The membrane extending from the tail to the hind legs is known as the interfemoral membrane. The medium-sized Rafinesque's big-eared bat is easily distinguished from other park bats by its very large ears and prominent lumps near the nose. The ears are 1 inch (25 mm) long and are joined at their base. These bats are dark brown above and white below. The interfemoral membrane and wings are unfurred.

left lateral view of skull and mandible	dorsal view of skull	ventral view of skull

• Range Maps

  North America	Great Smokies

• Great Smoky Mountains National Park: Rafinesque's big-eared bats are one of the most common bats in the park and have been recorded from elevations ranging from 1,530 feet to 2,400 feet. Harvey (1991) noted that the largest known hibernating colony (570 bats), as well as smaller maternity colonies, occupied the abandoned mines in the southwestern section of the park. On February 23, 1993, a survey by Park Service biologists revealed a total of 699 hibernating bats in one Eagle Creek Mine and 454 bats in Sugar Fork Mine.
  • Blount Co.: Blowhole Cave; Gregory Cave; Scott Gap Cave; Calf Cave No. 2.

  • Sevier Co.: Myhr Cave (1,530 feet); Sugarlands; Greenbrier.

  • Haywood Co.: Cataloochee (?) (see Harvey, 1987).

  • Swain Co.: Hazel Creek Ranger Station; Sugar Fork Mine #102; Eagle Creek Mines #107, #109, #110, and #111; Forney Creek CCC Camp (2,400 feet).

Rafinesque's big-eared bats roost in hollow trees, caves, mines, and buildings. Twenty-two individuals were found roosting in a discarded boiler 11 feet in diameter and 4 1/2 feet long lying on its side on a hillside near Eagle Creek (Linzey, 1995a).

Index

Natural History

• Reproduction
  Copulation in Rafinesque's big-eared bats, as with most bats that hibernate, takes place in autumn and winter. Females congregate in nursery colonies after emerging from the hibernaculum and give birth to a single young in late May or early June. Females have been observed carrying young approximately half as large as the parent on several occasions near park headquarters in 1950 (Linzey, 1995a).

• Longevity
  Rafinesque's big-eared bats may live as long as 10 years.

• Terrestrial Ecology
  The senses of sight and hearing are well developed in bats. Since most bats become active near dusk and are active much of the night, sight is of little importance in mavigation and in the capture of prey. Instead, they use echolocation, a system somewhat similiar to radar. They emit ultrasonic calls far above the range of human hearing that are reflected from objects ahead of them. They hear the echoes and are able to avoid obstacles and find food in total darkness. Different species can be distinguished by differences in the structure of their echolocation calls (Fenton and Bell, 1981).

  Big-eared bats usually roost singly rather than in clusters. They leave their roost well after dark and return before dawn. Their flight is slow, and they can hover in one place. During feeding maneuvers, the tail and wing membranes are used to capture and restrain prey. Some insects are captured by the tail membrane, which forms a pouch-like compartment. the bat must bend its head forward in order to grasp the insect with its teeth and take it into its mouth. Sometimes the bat may use its mouth to capture an insect from its wing.

  Eleven species of bats have been recorded in the park and all feed exclusively on insects. During the colder months when flying insects are unavailable, bats must either hibernate or migrate to warmer areas. Eight of our bats are known to hibernate. Only three - the red bat, hoary bat, and the silver-haired bat - are migratory. Bats have been seen flying over the park during every month of the year. When flying during the winter, however, they do not feed.

• Predators and Defense
  No predators recorded from the park.

• Parasites
  None recorded from the park.

• Transmittable diseases
  Bats are capable of transmitting two diseases to humans - rabies and histoplasmosis. Histoplasmosis is a disease caused by inhaling dust that contains contaminated spored. Tuttle (1988) stated: "Less than a half of 1 percent of bats contract rabies, a frequency no higher than that seen in many other animals. Like others, they die quickly, but unlike even dogs and cats, rabid bats seldom become aggressive." Bats do not attack when they get rabies; they just lie in one place. Although it is rare for humans to contract rabies from infected bats, persons handling them should be aware of this possibility.

• Text
  • Dr. Donald W. Linzey, Wytheville Community College - wclinzd@wcc.vccs.edu
  • Christy Brecht, Wytheville Community College - wcbrecc@wcc.vccs.edu

• Photographs
  • No photo obtained yet.

• Map development
  • Richard Schulz, Great Smoky Mountains National Park - richard_schulz@nps.gov

• Web page design & coding
  • Denise Lim, University of Georgia, Athens
  • John Pickering, University of Georgia, Athens

• Barbour, R. W. and W. H. Davis. 1969. Bats of America.Lexington: The University Press of Kentucky.

• Fenton, M. B. and G. P. Bell. 1981. Recognition of insectivorous bats by their echolocation calls. Journal of Mammalogy 62 (2): 233-243

• Harvey, M. J. 1987. Bat utilization of historic structures in the Cataloochee historic zone and of mines in the Sugar Fork and Eagle Creek watersheds, Great Smoky Mountains National Park. Report to National Park Service.

• Harvey, M. J. 1991. Survey for threatened and endangered mammals on the right-of-way of proposed segment 8D of the Foothills Parkway. Report to the Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee.

• Harvey, M. J., J. S. Altenbach, and T. L. Best. 1999 Bats of the United States. Little Rock: Arkansas Game and Fish Commission.

• Jones, C. 1977. Plecotis rafinesquii. Mammalian Species No. 69: 1-4. American Society of Mammalogists.

• Linzey, D. W. 1995a. Mammals of Great Smoky Mountains National Park. Blacksburg, Virginia: The McDonald & Woodward Publishing Company, Inc.

• Linzey, D. W. 1995b. Mammals of Great Smoky Mountains National Park-1995 Update. Journal of the Elisha Mitchell Scientific Society 111(1): 1-81.

• Linzey, D. W. 1998. The Mammals of Virginia. Blacksburg, Virginia: The McDonald & Woodward Publishing Company, Inc.

• Lynch, M. R. and C. Jones. 1999. Rafinesque's big-eared bat. Pages 119-121. In: D.E. Wilson, and S. Ruff (eds.). The Smithsonian Book of North American Mammals. Washington, D. C.: Smithsonian Institution Press.

• Tuttle, M. D. 1988. America's Neighborhood Bats. Austin: University of Texas Press.